Australia appears set to legalize the growing of marijuana for medical use nationwide. A bill introduced to parliament Wednesday (Feb. 10) by the Liberal Party would amend the Narcotic Drugs Act 1967. It looks guaranteed to become law, as the main opposition party immediately pledged support for it.

Under the proposal a national licensing and permit scheme would be established for supplying medical cannabis to patients with painful and chronic conditions. It’s expected to become law by the...